The oldest existing "books" of Tarot Cards are those from 1840-1842. Many theories exist about the origins of the Tarot. During different periods of history, occult studies were either freely available to all or guarded as a secret, depending upon the prevailing authorities or the attitude of the existing culture towards occult knowledge. One of these "books" was supposedly based on the legendary "Book of Thoth," derived from the mystery schools of Egypt. Gypsies are said to have carried the cards to Europe. "Gypsy" is considered a corrupt form of "Egyptian." Considered by the church to be "the devil's picture book," the cards were quickly condemned by the Catholic Church as heretical. Even to possess them was a dangerous act. Though we can only speculate on their origins, the Tarot images are inextricably linked to ancient beliefs, mythologies and religious systems, such as the Hebrew Cabala. Others, notably Pythagoras, believed that letters and numbers are in themselves divine beings possessing extraordinary powers.